A sprocket[1] or sprocket-wheel[2] is a profiled wheel with tooth, or cogs,[3][4] that mesh with a chain, monitor or other perforated or indented material.[5][6] The name ‘sprocket’ applies generally to any wheel where radial projections engage a chain moving over it. It is distinguished from a equipment in that sprockets are never meshed together directly, and differs from a pulley in that sprockets have teeth and pulleys are clean.

Sprockets are found in bicycles, motorcycles, cars, tracked vehicles, and other machinery either to transmit rotary motion between two shafts where gears are unsuitable or to impart linear motion to a monitor, tape etc. Perhaps the most typical form of sprocket may be found in the bicycle, in which the pedal shaft carries a huge sprocket-wheel, which drives a chain, which, subsequently, drives a little sprocket on the axle of the trunk wheel. Early automobiles had been also largely powered by sprocket and chain mechanism, a practice mainly copied from bicycles.

Sprockets are of various designs, a maximum of efficiency becoming claimed for every by the originator. Sprockets typically don’t have a flange. Some sprockets used with timing belts have flanges to keep the timing belt centered. Sprockets and chains are also used for power transmission from one shaft to some other where slippage isn’t admissible, sprocket chains being used rather than belts or ropes and sprocket-wheels rather than pulleys. They can be run at high speed plus some kinds of chain are so built as to be noiseless also at high speed.